Citation and License

Genome Biology 2012, 13:R101
doi:10.1186/gb-2012-13-11-r101

Published: 15 November 2012

Abstract

Background

Recent advances in sequencing technologies have enabled metagenomic analyses of many
human body sites. Several studies have catalogued the composition of bacterial communities
of the surface of human skin, mostly under static conditions in healthy volunteers.
Skin injury will disturb the cutaneous homeostasis of the host tissue and its commensal
microbiota, but the dynamics of this process have not been studied before. Here we
analyzed the microbiota of the surface layer and the deeper layers of the stratum
corneum of normal skin, and we investigated the dynamics of recolonization of skin
microbiota following skin barrier disruption by tape stripping as a model of superficial
injury.

Results

We observed gender differences in microbiota composition and showed that bacteria
are not uniformly distributed in the stratum corneum. Phylogenetic distance analysis
was employed to follow microbiota development during recolonization of injured skin.
Surprisingly, the developing neo-microbiome at day 14 was more similar to that of
the deeper stratum corneum layers than to the initial surface microbiome. In addition,
we also observed variation in the host response towards superficial injury as assessed
by the induction of antimicrobial protein expression in epidermal keratinocytes.

Conclusions

We suggest that the microbiome of the deeper layers, rather than that of the superficial
skin layer, may be regarded as the host indigenous microbiome. Characterization of
the skin microbiome under dynamic conditions, and the ensuing response of the microbial
community and host tissue, will shed further light on the complex interaction between
resident bacteria and epidermis.